1. Field of the Invention
The present invention relates to a method of fabricating a bipolar junction transistor. More particularly, the present invention relates to a method of fabricating a complementary bipolar junction transistor.
2. Description of the Related Art
Bipolar junction transistors with higher current driving capacity and faster operating speed have been increasingly replacing MOS field effect transistors in specific parts of individual products in recent years. Also, a complementary bipolar transistor in which a PNP bipolar junction transistor and an NPN bipolar junction transistor are integrated on a silicon substrate is being employed for realizing high-speed data processing and high performance.
In a conventional complementary bipolar junction transistor, a P-type emitter electrode of a PNP bipolar junction transistor and an N-type emitter electrode of an NPN bipolar junction transistor are separately formed. In more detail, after the N-type emitter electrode of the NPN bipolar junction transistor is formed on a first portion of a silicon substrate, the P-type emitter electrode of the PNP bipolar junction transistor is formed on a second portion of the silicon substrate. The separately-formed N-type emitter electrode of the NPN bipolar junction transistor and the P-type emitter electrode of the PNP bipolar junction transistor complicate a fabricating process and impede precise fabricating of the complimentary bipolar junction transistor.